\paragraph{BPEL}
The BPEL file specifies the chain of operations of the various configurations and experiments. We report below a fragment of such file extracted from the pipeline of WebML Experiment C (Area granularity, Multi-Field Weighted Index), specifying an activity to be performed:

\lstset{
language=XML,
breaklines=true,                % sets automatic line breaking
breakatwhitespace=false,        % sets if automatic breaks should only happen at whitespace
basicstyle=\footnotesize,	% the size of the font
frame=single,
backgroundcolor=\color{grey}
}

\begin{lstlisting}
<extensionActivity>
  <proc:invokePipelet name="invokeAnalyzerSubstitutionPipelet">
    <proc:pipelet class="it.polimi.mdir.webml.pipelet.AnalyzerSubstitutionPipelet" />
    <proc:variables input="request" /> 
    <proc:configuration>
      <rec:Val key="coreName">webml_C</rec:Val>
      <rec:Val key="fieldType">content_analysis</rec:Val>
    </proc:configuration>
  </proc:invokePipelet>
</extensionActivity>
\end{lstlisting}

This is an example of an \emph{invoke} activity. The \emph{proc:invokePipelet} tag specifies the name of this activity, while the \emph{proc:pipelet} tag specifies the pipelet to be called. \emph{proc:variables} indicates the name of the workflow variable where the SMILA records are located. After that, inside the \emph{proc:configuration} tag it is possible to specify the name and the value of some configuration variables specific to this activity. These variables will take the form of a SMILA record and are read using its conventions.

You can see the graphical representation of the whole pipeline from which this activity was extracted in Figure \ref{fig:webmlpipeline_C} as it is displayed by the Eclipse BPEL Designer, a tool that can be used to graphically design pipelines.

\begin{figure}[ht]
  \begin{center}
	\includegraphics[width=0.8\textwidth]{./pictures/webmlpipeline_C}
	\caption{The pipeline of the Experiment C for WebML displayed by the Eclipse BPEL Designer.}
	\label{fig:webmlpipeline_C}
  \end{center}
\end{figure} 

\paragraph{Case-specific configuration files}
These files configure variables and settings specific to one of the two case studies. It takes the form of a simple Java \emph{properties file}. The example below depicts the one for the WebML case study. Each entry is explained by the commented lines that begin with ``\#''.

\begin{lstlisting}
#Path where to find the WebML projects (parent folder)
WEBML_PATH=C:/WebML_models_012/

#Path where to put the .xmi files in output.
OUTPUT_PATH=../it.polimi.mdir.webml/output/

#Path where the WebML queries are located (parent folder)
WEBML_QUERY_PATH=../webmlQueries/

#---------------------#
#Weights configuration#
#---------------------#

#weightmap
siteview=1.3
area=1.2
page=1.1
unit=1.0
link=0.8
\end{lstlisting}
